Transmitting typewriter apparatus



Jan. 23, 1962 R. B. JOHNSON ETAL 3,018,332

TRANSMITTING TYPEWRITER APPARATUS Filed June 25, 1958 2 Sheets-Sheet 1 AMPLIFIER 1 I I l TAPE PUNCH F/ 2 REYNOLD B. JOHNSON JACOB J. HAGOP/A/V EMS Jan. 23, 1962 R. B. JOHNSON ETAL 3,01

TRANSMITTING TYPEWRITER APPARATUS Filed June 25, 1958 2 Sheets-Sheet 2 ilnited States Patent Ofitice 3,018,332 Patented Jan. 23, 1962 3,018,332 TPANSMITTMG TYPEWRH'ER APPARATUS Reynold B. .lohnson, Palo Alto, and Jacob J. Hagcpian,

San Jose, Calif., assignors to International Business Machines Corporation, New York, NFL, a corporation of New York Filed June 25, 1958, Ser. No. 744,581 8 Claims. (Cl. 178-17) This invention relates in general to transmitting typewriter apparatus and relates more particularly to such apparatus wherein a typewriter may be employed to generate coded output signals simultaneously with the typing operation.

There have been numerous proposals for modifying conventional typewriters so as to produce from these typewriters output signals indicative of the difierent characters being typed. These output signals may then be utilized in some auxiliary apparatus, such as a slave typewriter or a printing mechanism of some sort. One of such solutions utilizes electrical contacts which are operated by the diiierent keys or" the typewriter and which control auxiliary relays to drive some type of output device. In another system a typewriter is provided with key-operated permutation bars which are utilized to actuate combinations of electrical contacts for producing output signals to drive an output device. A further system utilizes optical means in the form of shutters which are attached to the difierent key levers for interrupting a beam of light when the key is actuated. The shutters are provided with combinations of openings corresponding to the code designations for the difierent characters being typed, and the coded light output pulses may be utilized to drive or control some output apparatus.

While the above prior art systems have been eliective to provide output signals from a typewriter corresponding to the character typed, they have been in general unsatisfactory from an operational standpoint, since they all involve either an extensive and inconvenient modification of existing typewriters or a considerable amount of additional apparatus on a new typewriter. Further, the optical system described above requires the accurate positioning of the light source and shutter bars within the typewriter housing, thus adding to the complexity and maintenance problems of the machine.

Broadly, the present invention contemplates apparatus for providing output signals from a typewriter, in which each of the typewriter type bars is provided on the head thereof adjacent the typeface with a coded representation of the particular character. A transducer disposed adjacent the platen of the typewriter senses the coded representations upon actuation of the typewriter key when the individual typefaces are near or in contact with the material being typed. In one embodiment of the invention, the coded representations of the difierent characters are provided by means of a number of elements of magnetic material arranged in a positional code on the head of the type bar, and the transducer is in the form of a corresponding number of electromagnetic coils which are in register with the difierent positions of the magnetic elements when the key is actuated. Those coils which, upon actuation of a key, are in register with a position having a magnetic element therein have voltages induced therein so that the transducer output signal contains pulses corresponding to the coded representation of the actuated key. This output signal may be supplied to any suitable utilization apparatus, such as a tape punch, recorder, slave typewriter or any other suitable output device.

In another embodiment of the present invention, the coding elements in the head of the type bar are in the form of openings extending through the head so as to selectively permit light from a source to pass therethrough. The number and positions of the openings correspond to the code designation for the particular character represented by that key. The light passing through the selected openings falls on a group of light sensitive elements which are in register with the head of the type bar and which produce an output signal containing pulses corresponding to the coded representation of the typed character.

Any suitable code may be utilized to represent the different characters on the typeface, and the coded output pulses from the transducer may be produced either simultaneously or sequentially from the diiierent sensing elements. In the case of simultaneous production, the coding elements are sensed simultaneously by the different sensing elements and the corresponding output pulses are produced on a number of different channels. For sequential production, the coding elements are sensed sequentially by the different sensing elements and the output pulses may be supplied serially from the different sensing elements to a single output channel.

The present invention may be put into practice either by modifying an existing typewriter so as to provide it with the coding elements and appropriate transducers, or by constructing a new typewriter in accordance with these teachings. The present invention has the advantage that it does not require any modification of or additions to the actuating mechanism of the typewriter, since it may be carried out by disposing a transducer adjacent the platen and by securing to the heads of each of the type bars a device having the required coded representations therein.

It is therefore an object of the present invention to provide an improved transmitting typewriter apparatus.

It is a further object of the present invention to provide a transmitting typewriter apparatus in which coded representations of the different type characters are contained in the head of the type bars adjacent the typeface.

It is an additional object of the present invention to provide a transmitting typewriter apparatus in which coded representations of the difierent characters being typed are carried on the heads of the dilierent type bars and these representations are sensed by a transducer disposed adjaccnt the typewriter platen.

It is an additional object of the present invention to provide a transmitting typewriter apparatus which is simple and inexpensive and which may be utilized on a conventional typewriter without requiring extensive modification.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings which disclose, by way of example, the principle of the invention and the best mode which has been contemplated of applying that principle.

In the drawings:

FIG. 1 shows in perspective form a portion of a typewriter equipped with a'magnetic transducer and magnetic coding representation on several keys thereof.

FIG. 2 diagrammatically illustrates the circuits of the transducer of FIG. 1 in connection with apparatus for utilizing the transducer output.

FIG. 3 is a schematic showing of a transducer in ac cordance with the present invention utilizing optical sensing elements.

FIG. 4 illustrates a typewriter type bar having coding representations therein suitable for use with the transducer illustrated in FIG. 3.

FIG. 5 illustrates a type bar having an alternative arrangement of coding representations thereon.

Referring to FIG. 1, reference character 10 generally designates a typewriter on which the present invention may be utilized. Typewriter 10 includes a platen 11 over which the paper passes and on which the paper is supported at the time of typing the different characters. The transducer 12 of the present invention is disposed adjacent the platen 11 so as to sense the coding representations on the different type bars when the keys are actuated. In the embodiment illustrated in FIG. 1, transducer 12 has a plurality of magnetic sensing elements which sense the coded magnetic representations on the different type bars and produce electrical output signals indicative of the particular character typed. These sensing elements may be in the form of electromagnetic coils wound on suitable magnetic cores, and as shown in FIGS. 1 and 2, a plurality of coils 13a, 14a, 15a, 16a, 17a, 18a and 19a may be provided on their associated cores 13b, 14b, 15b, 16b, 17b, 18b and 19b.

7 The sensing elements are arranged in a configuration which is determined by the particular core being used to represent the diiferent typed characters, and in the particular embodiment illustrated in FIG. 1 these sensing elements are disposed in a seven-element column, corresponding to a seven-bit code commonly used in data processing machinery. In the preferred embodiment of the present invention the transducer includes the sensing elements 13 through 19 described above, together With a similar series of electromagnetic coils and cores symmetrically disposed with respect to the first series so as to form an opening through which the head of the actuated type bar passes. This additional series of electromagnetic coils 13a, 14a, 15a, 16a, 17a, 18a and 19a, together with the associated cores 13b, 14b, 15b',.16b', 17b, 18b and 19b are disposed as shown in FIG. 1 to form the opening into which the head of the actuated type bar passes. As best shown in FIG. 2, the associated pair of coils of each sensing element is preferably connected in series-aiding connection so that the electromotive forces generated therein in response to passage of a magnetic element are combined.

The coded representations of the different characters being typed may be provided by any suitable magnetic elements on the difierent type bars adjacent the heads thereof. These representations may be provided on all of the keys or, if desired, may be provided on only selected ones of the keys, such as those representing the digits. In the embodiment illustrated in FIG. 1, the coded representations are selectively provided in different ones of a plurality of openings 13c, 14c, 15c, 16c, 17c, 18c and 190 in the head of the type bar adjacent the typeface. These openings are selectively provided with magnetic elements in the positions corresponding to the code designations for the particular character associated with the typewriter key. As shown in FIG. 1, a type bar 26 has magnetic elements 25 in the positions corresponding to openings 13c and 190, representing the seven-bit code designation for the character on the typeface of type bar 26. Similarly, another type bar 27, shown in FIG. 1 in typing position with the coding elements on the head thereof positioned in the opening between the coils of transducer 12, is provided with magnetic coding elements 25 in the code positions corresponding to openings 16c and 180, representing the sevenbit code designation for that particular character.

The magnetic elements 25 may be provided in the heads of the different type bars by any suitable means, such as by drilling holes in the heads and inserting the magnetic elements therein. Alternatively, the magnetic elements may be provided in the heads of the type bars by means of a member 28 which is provided with the coding openings and magnetic elements therein and which is adapted to slip over the head of the type bar and to be secured thereto by any suitable meanssuch as crimping or cementing. Member 28 may' be of any suitable material, such as plastic, in which the openings 13c through 19c are drilled and into which the magnetic elements 25 are selectively inserted. Member 28 preferably has dimensions such that it may be mounted on some or all of the type bars of a conventional typewriter without, interfering with the clearance between the different heads When the keys are at rest.

The difierent openings 130 through 190 in member 28 are designed to be in register with the associated sensing elements 13 through 19 when the type bar is in the actuated position, as shown by type bar 27 in FIG. 1, to produce an output pulse in those sensing elements which are in register with a magnetic element 25. By using pairs of series-aiding coils on opposite sides of the transducer opening, the efiect of variations in the position of the actuated type bar heads relative to the sensing elements may be reduced so that the sensing element output pulses have a substantially constant amplitude.

The output signal from transducer 12, comprising the pulses from the different sensing elements, may be utilized in any suitable manner. As shown in FIG. 2, one such method of utilizing the output pulses is to drive the punching elements of a tape punch device 30 which punches on a tape 31 a coded representation of the particular character typed. In the embodiment shown in FIGS. 1 and 2 it is assumed that the output pulses from the difierent sensing elements within the transducer are produced simultaneously, i.e., each of openings 130 through 19c is in register with its associated sensing element at substantially the same time so that the output pulses from the sensing elements are produced at substantially the same time. As shown in FIG. 2, these output pulses from the different sensing elements are supplied through an amplifier 32 to the driving elements of tape punch 39. The amplified pulses from amplifier 32 control a punch mechanism for producing coded holes or openings in tape 31 as the tape moves past the punch. Thus, the openings punched in tape 31 in a direction perpendicular to the direction of travel of the tape will be a coded representation of the particular character typed on typewriter 10.

FIG. 3 illustrates an additional embodiment of the invention utilizing optical means as sensing elements for the transducer. The sensing elements may include a plurality of photosensitive devices, such as photocells,

;33a, 34a, 35a, 36a, 37a and 38a which are optically separated from each other and which are adapted to be selectively energized from a suitable light source such as a bulb 41. Source 41 is disposed on the opposite side of the transducer type bar opening from the photocells so that light is projected through a series of apertures 33b, 34b, 35b, 36b, 37b and 38b to the photocells. A type bar 43 having the required coding elements in the head thereof for use with the transducer shown in FIG. 3 is illustrated in FIG. 4. Type bar 43 is provided with a plurality of openings 33c, 34c, 35c, 36c, 37c and 38c in the head thereof. These openings extend through the head of type bar 43 so that light may be transmitted therethrough. Openings 33c through 380 are disposed in staggered form on the head of the type bar, so that opening 33c passes its associated sensing element 33:: first, then openings 34c, 350, etc., to produce a sequential sensing of the openings 330 through 38c. Selected ones of the openings 330 through 38c are provided with opaque material 44 therein so as to block the transmission of light therethrough, the location of these opaque elements representing the code designation for the particular character on that typewriter key.

The head of type bar 43 is also provided at the top thereof with a gating opening 450 which is associated with a photocell 45a. Gating opening 450 is disposed on the type bar head so as to pass photocell 45a, when the key is actuated, before any of the openings 33c through 38c are in register with their associated photocells. The gating pulse produced by photocell 45a in response to light transmitted through opening 450 is supplied to a gating network 46 which controls an amplifier 47. Network 46 operates to energize amplifier 47 for a predetermined time, corresponding to the time of passage of openings 33c through 380 past photocells 33a through 38a, and then deenergize the amplifier until the next gating pulse from photocell 45a.

In operation, when a key is actuated, the head of the type bar passes between the photocells on one side and the light source represented by lamp 41 and the associated apertures 33!) through 38b on the other side. The head first passes between aperture 45b and photocell 45a so that light passing through gating opening 450 produces a pulse in photocell 45a. This pulse is supplied to gating network 46 where it serves to energize amplifier 47. Then, as each of openings 33c through 380 sequentially passes its associated photocell 33a through 38a, light from source 41 is either transmitted through the particular opening, or blocked where the openings are provided with opaque material 44. The light pulses reaching photocells 33a through 38a are converted into electrical signals and supplied serially through a single channel to amplifier 47 where they are amplified and supplied to some output device (not shown). At the end of the gating period for gating network 46, which period corresponds to the time required for all the openings 330 through 38c to pass the associated photocells on the forward movement of the actuated type bar, amplifier 47 is deenerg-ized to prevent the generation of output signals on the return movement of the actuated type bar.

FIG. illustrates the head of a type bar 49 using a code different from the sevenbit code illustrated earlier to better utilize the area available on the type bar head. As shown, type bar 49 is provided on the head thereof with a plurality of coding elements 50c which are arranged in a 3 X 3 matrix. Coding elements 500 may be magnetic elements similar to those illustrated in connection with the embodiment of FIGS. 1 and 2, or these coding elements may be openings for the passage of light, as illustrated in the optical embodiment of FIGS. 3 and 4. It will be understood that the transducer associated with type bar 49 and coding elements 50c will have sensing elements so disposed as to be in register with the elements 500 upon actuation of the key.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to the preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art, Without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

1. In combination, a typewriter having a platen and a plurality of type bars, said type bars having on the heads thereof adjacent the typeface a plurality of coding elements having coded positions corresponding to the particular character on said typeface, and a transducer positioned adjacent said platen astride the path of each of said heads when said type bars are actuated, said transducer being responsive to the positions of said coding elements on said heads for producing an output signal upon actuation of any one of said type bars corresponding to the coded representation of the char-acter on the actuated type bar.

2. In combination, a typewriter having a platen and a plurality of type bars, said type bars having on the heads thereof adjacent the typeface a plurality of magnetic coding elements having coded positions corresponding to the particular character on said typeface, and an electromagnetic transducer positioned adjacent said platen astride the path of each of said heads when said type bars are actuated, said transducer being responsive to the positions of said coding elements on said heads for producing an output signal upon actuation of any one of said type bars corresponding to the coded representation of the character on the actuated type bar.

3. In combination, a typewriter having a platen and a plurality of type bars, said type bars having on the heads thereof adjacent the typeface a plurality of coding openings having positions corresponding to the particular character on said typeface, and a transducer positioned adjacent said platen astride the path of each of said heads when said type bars are actuated, said transducer including a light source on one side of said coding openings and light sensitive means on the other side of said openings responsive to light transmitted through said openings for producing an output signal upon actuation of any one of said type bars corresponding to the coded representation of the character on the actuated type bar.

4. In combination, a typewriter having a platen and a plurality of type bars, said type bars having on the heads thereof adjacent the typeface a plurality of coding opena ings having positions corresponding to the particular character on said typeface, and a transducer positioned adjacent said platen astride the path of each of said heads when said type bars are actuated, said transducer including a light source on one side of said coding openings and light sensitive means on the other side of said openings, said light sensitive means being responsive to light transmitted sequentially through said openings for producing an output signal upon actuation of any one of said type bars containing pulses corresponding to the coded representation of the character on the actuated type bar.

5. In combination, a typewriter having a platen and a plurality of type bars, said type bars having on the heads thereof adjacent the typeface a plurality of coding openings having positions corresponding to the particular character on said typeface, and a transducer positioned adjacent said platen astride the path of each of said heads when said type bars are actuated, said transducer including a light source on one side of said coding openings and light sensitive means on the other side of said openings, said light sensitive means being responsive to light transmitted simultaneously through said openings for producing an output signal upon actuation of any one of said type bars containing pulses corresponding to the coded representation of the character on the actuated type bar.

6. In combination, a typewriter having a platen and a plurality of type bars, said type bars having on the heads thereof adjacent the typeface a plurality of magnetic coding elements having positions corresponding to the particular character on said typeface, and a transducer positioned adjacent said platen astride the path of each of said heads when said type bars are actuated, said transducer having a plurality of sensing elements corresponding to the number of said positions for producing an output signal upon actuation of any one of said type bars corresponding to the coded representation of the character on the actuated type bar.

7. In combination, a typewriter having a platen and a plurality of type bars, said type bars having on the heads thereof adjacent the typeface a plurality of magnetic coding elements having positions corresponding to the particular character on said typeface, and a transducer hav-. ing a plurality of sensing elements corresponding to the number of said positions positioned adjacent said platen astride the path of each of said heads when said type bars are actuated, said sensing elements being responsive to sequential passage of said magnetic coding elements for producing an output signal upon actuation of any one of said type bars containing pulses corresponding to the coded representation of the character on the actuated type bar.

8. In combination, a typewriter having a platen and a plurality of type bars, said type bars having on the heads thereof adjacent the typeface a plurality of magnetic coding elements having positions corresponding to the particular character on said typeface, and a transducer having a plurality of sensing elements corresponding to the References Cited in the file of this patent UNITED STATES PATENTS Hofgaard Dec. 28, 1943 Hofgaard June 6, 1944 Linger June 19, 1956 Jones May 7, 1957 Minna 

